Collaborative bookmarking is a growing phenomenon within the world-wide web. Users of a collaborative bookmarking site contribute to the site by associating, or “tagging” uniform resource locators (URLs) for web-accessible content with descriptive phrases and key words, or tags. A tag is a non-hierarchical keyword or term assigned to a piece of information (such as an internet bookmark, digital image, or computer file). This kind of metadata helps describe an item and allows it to be found again by browsing or searching. Tags are chosen informally and personally by the item's creator or by its viewer, depending on the system. On a website in which many users tag many items, this collection of tags becomes a folksonomy, also known as social classification, social indexing or social tagging.
The contributions of the site users is typically displayed as a single page, random arrangement of tags commonly referred to as a tag cloud. This is exemplified by collaborative bookmarking sites such as delicious.com and flickr.com. Further examples of collaborative bookmarking solutions include IBM's Dogear, the Onomi social bookmarking system, and the Cogenz enterprise tagging solution.
Collaborative bookmarking systems used in the corporate environment, such as IBM's dogear and the Onomi bookmarking system, have proven valuable for: 1) providing research analysts with a place to share research findings; 2) fueling expertise finding and user profiling; 3) helping to form and support social networks around interest areas; 4) enhancing the value of other information retrieval and aggregation capabilities on a company's intranet; and 5) influencing or augmenting corporate subject taxonomy strategies.
These systems share a number of common features. They allow individuals to create personal collections of bookmarks and easily share their bookmarks with others. These centrally stored collections can be accessed from web-connected machine. These systems all have the ability to display tag clouds that represent the contributions of all of a collaborative bookmarking site's users. Tags that are explicitly entered by the user for each bookmark allow the individual user to organize and display the collection with meaningful labels. Furthermore, multiple tags allow bookmarks to belong to more than one category, a limitation of traditional hierarchically organized folders found in most web browsers. Although bookmark collections are personally created and maintained, they are typically visible to others. A number of user interface elements allow social browsing of the bookmark space. For example, user names are “clickable” links; clicking on a name reveals the bookmark collection for that user. This allows someone to get a sense of the topics of interest for a particular user. Similarly, tags are also clickable, and when selected will result in a list of all bookmarks that share that tag. This is a useful way to browse through the entire bookmark collection to see if it includes information sources of interest.
These systems also have the ability to display the relative number of contributions and/or activity of contributions by varying the weight, size, color, and style of the fonts used to display tags within a tag cloud. For example, a tag that refers to twice as much content as another tag may be shown using a larger font that the other tag.
Moreover, there are other systems, such as the Mooter search engine, that enable the automated discovery and presentation of related topics within a group of web-accessible content but these rely on automated topic discovery (topics are analogous to tags) through parsing of web content. This results in a narrow set of topics that does not represent the wide variety of viewpoints observed in a social bookmarking solution.
What these systems all lack is the ability to present users with tags that are related to a tag of interest. For example, suppose a user is searching for tags related to the topic of chairs. Current systems have no ability to relate this to the topic of recliners and thus require the user to know that a recliner is a specialization of the general topic of chairs.